Disc hemorrhage with low intra-ocular pressure, an evidence-based approach

Abstract

Purpose To document a case of low intraocular pressure (IOP) that developed a disc hemorrhage (DH) and subsequent corresponding pre-perimetric retinal nerve fiber layer (RNFL) loss on spectral domain optical coherence tomography (SDOCT). Current concepts on etiology and evidence-based management of optic nerve hemorrhages in glaucoma and normo-tension cases are discussed. Methods Case report. A superior temporal flame shaped hemorrhage was observed at the disc margin OD of a 57-year-old female with unremarkable health. A SDOCT exhibited a normal RNFL. Throughout three years the patient developed progressing superior temporal RNFL on SDOCT. Humphrey visual field (VF) was normal. The cup/disc ratio (c/d) was 0.7/0.7 with slight superior thinning and corresponding RNFL defect on photos compared to those at the initial occurrence of the disc hemorrhage. The highest recorded IOP over all visits was 13 mm Hg. # Conclusion Evidence based documentation indicates that the occurrence of a DH may lead to RNFL loss or progression of VF loss. Although lamina cribrosa (LC) defects are concomitantly associated with DH, the causality may be indirectly related. The rate of RNFL loss may be reduced in normal tension patients by lowering intraocular pressure. Further medical treatment consequently may be beneficial. Bruch’s membrane opening minimum rim width demonstrates a greater rate of change compared to that of RNFL and therefore may help identify earlier glaucoma stages. Vascular and laminar damage may have a similar etiological mechanism. A proposed membrane glymphatic theory of primary glaucoma may clarify the currently unidentified underlying mechanisms that lead to glaucoma progression.